000
FXUS61 KOKX 151138
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
738 AM EDT Thu Jun 15 2023
.SYNOPSIS...
Weak high pressure positions itself south of the area today and
tonight. A frontal system and associated low pressure approach
Friday, with the frontal system passing through Friday night.
Weak low pressure remains in the area Saturday into Sunday. High
pressure then briefly returns Sunday night into Monday. Another
low moves into the area Tuesday and remains into midweek.
&&
.NEAR TERM /THROUGH TONIGHT/...
Mostly sunny conditions for this morning across southern
portions of the CWA, and actually much of the CWA. Northern most
sections will have more in the way of clouds which have been
rotating around the closed upper level low.
The closed upper level low lifts towards Northern New England
today. This will leave behind a flatter flow within the upper
trough. The flat flow and little to no lift supports a dry
forecast. BUFKIT soundings continue to indicate a shallow layer
of higher RH around and just above 5kft. Thus, other than some
diurnally driven cu, expect mostly sunny skies to give way to
partly cloudy skies. Afterwards, the models continue to show
another vort max / shortwave digging and diving south on the
backside of the trough over the Great Lakes and Ohio Valley
Thursday night. This should eventually redevelop the trough and
upper level low over the northeast. Therefore clouds should
begin to increase late Thu. night in advance of the redeveloping
trough.
Most highs on Thursday will be close to normal in the upper 70s to
around 80 degrees. Lows Thursday night with mostly clear to partly
cloudy skies will range in the middle and upper 50s across the
interior, to the lower and middle 60s in the NYC metro and mainly
around 60 along coastal sections.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
With the upper level low and mid level forcing approaching Friday
morning look for a good amount of cloud cover. There is some
uncertainty on precise timing of the arrival of the forcing
mechanisms to generate shower and potentially embedded t-storm
activity. Taking a model consensus approach yields likely showers
with a t-storm chance towards the afternoon and evening. At this
time it appears that much of the instability will be more elevated
than surface based, but this could change if more sunshine can get
through earlier in the day. Thus the current thinking is that
thunderstorm activity should primarily be sub severe. Have kept
out any enhanced wording at this time, but small hail and gusty
winds may be included with subsequent updates. The 500 mb
height minimum then positions itself over the area Fri night
into early Sat am. Although there will be the loss of diurnal
heating into Fri night, there will likely still be enough
forcing to drive high end chance to low end likely showers.
Temperatures should be below normal Friday with highs mainly in the
middle and upper 70s due mainly to more pronounced cloud cover. Lows
Friday night will be more of the same with lows primarily in the
middle and upper 50s across the interior and more rural locations,
and near 60 or in the lower 60s for the NYC metro and along coastal
communities.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Ensemble means (GEFS/EPS) continue to depict a blocky pattern and
mean troughing over the eastern CONUS with a series of cutoff lows
moving through New England. Ridging then tries to build in from the
central plains by the end of next week but falls short, with mean
troughing shifting slightly east, but still influencing the area.
Thus, continued near to below normal temperatures and unsettled
weather for the long term. The NBM was followed closely for this
update.
Saturday into Sunday looks to be the most active day(s) at this
point. A deep upper low advertised by the global models approaches
the local area with an attendant sfc low and cold front passing
through the area by Saturday afternoon. Precipitation chances
increase through the day on Saturday as the cold front and upper low
approach, with model soundings showing around ~500 J/kg of MUCAPE
and 20-30kts of bulk shear. So thunderstorms are likely for the area
Saturday afternoon as well, with timing and coverage coming into
better focus over the next few days as CAMs cover the timeframe. The
CSU Machine Learning Probabilities had a 5% severe probability for
parts of the area, but have backed off this on the most recent run.
NBM probabilities of (any) thunder are in the 40-50% range for
Saturday afternoon and have increased slightly, especially over the
Lower Hudson Valley and SW CT over the past few cycles.
The low and associated cold front move east of the area by early
Sunday, though the upper low is slow to move out. Thus, Sunday
looks to be cloudy and showery--at least for the first part of the
day. Drier air advects in behind the system by Sunday night, and
with weak ridging aloft, Monday looks to be dry and seasonable.
The Tuesday - Thursday period again looks unsettled, with an upper
low approaching from the mid south, along with a series of vort
maxes from New England. Precipitation chances again increase
Tuesday through late Wednesday.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
Weak high pressure approaches from the southwest.
VFR through the TAF period.
WSW winds 10-15 kts with gusts up to 20kts through 00Z.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Gusts this afternoon may be more occasional than frequent.
OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY...
Thursday night: VFR.
Friday: Mainly VFR in the morning with a chance of showers, then
showers bcmg likely with chc tstms and MVFR in the afternoon.
Sat-Sun: VFR becoming MVFR with chc PM shra/tstm both days
Monday: Mainly VFR, slight chc PM shra.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
The winds will be mainly out of the west today with with ocean seas
3 to 4 ft today, and closer to 3 ft tonight. Ahead of the next
approaching frontal system on Friday look for more of a southerly
flow with ocean seas remaining around 3 ft. The winds will then
shift to the west later Fri night with sub small craft conditions
from Saturday through Monday with weak low pressure in the
vicinity Saturday and Sunday, and weak high pressure building in
for Monday.
&&
.HYDROLOGY...
No hydrologic impacts are expected through mid next week.
&&
.TIDES/COASTAL FLOODING...
There is a moderate risk of rip currents today and Friday.
Minor coastal flood benchmarks may be approached for the
western south shore back bays of Queens and Nassau Friday and
Saturday evening. At this time advisory level coastal flooding
is not anticipated.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JE/DBR
NEAR TERM...JE
SHORT TERM...JE
LONG TERM...DBR
AVIATION...DBR
MARINE...JE/DBR
HYDROLOGY...JE/DBR
TIDES/COASTAL FLOODING...